Flow-indicating device and associated mechanism and method

ABSTRACT

A flow-indicating device is provided, comprising a tubular body adapted to direct a flow therethrough. The body has opposed ends, with one end being a downstream end, and has a flow element disposed therein. A shaping block is operably engaged with the body so as to form a constricted portion between the ends, the constricted portion of the body defining a constricted orifice having a downstream side. The constricted orifice is configured to prevent the flow element from passing therethrough. The flow element is disposed on the downstream side of the constricted portion and is configured to engage the constricted orifice when the flow is below a flow rate and to move toward the downstream end of the body as the flow increases over the flow rate to thereby indicate the flow through the body. A sensor may be operably engaged with the shaping block between the constricted portion and the downstream end of the body, wherein the sensor is configured to produce a signal in response to the flow element moving toward the downstream end of the body as the flow increases, or the flow element may be viewed through a transparent shaping block or a slot defined by the shaping block. An associated mechanism and method are also provided.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to flow indicating devices and, moreparticularly, to a simplified flow-indicating device and associatedmechanism and method.

2. Description of Related Art

Flow-indicating devices for high-purity fluids may often be expensiveand complicated devices due to the construction and configurationfactors which must be taken into account so as to minimize contaminationof the fluid. In some instances, in order to automatically obtain adesired flow of such a high-purity fluid, a suitable rotometer(otherwise referred to herein as a flow meter) is used with a separateoptical detector or sensor for detecting when the flow has reached acertain level. That is, the flow meter typically includes a flow elementwhich is moved along a graduated scale as the flow increases. Theoptical sensor is disposed externally to the flow meter and senses whenthe flow has reached a certain level by detecting the position of theflow element. However, some rotometers may require extensive machiningand fitting of components to provide a calibrated flow. Accordingly, dueto the nature of such a rotometer, entire units must be used for eachapplication. For example, a rotometer used one application for one fluidmay not be readily and interchangeably used in a second application fora second fluid due to cross-contamination concerns.

In other situations, the rotometers may include components which, as aresult of the design of the flow meter, contact the fluid or otherwisecomprise a pathway between the external environment and the fluidflowing within the flow meter, thereby introducing the risk of fluidcontamination. Further, since the optical sensor is a separate componentwhich must be suitably secured in correspondence with the flow meter inorder to sense a particular and calibrated flow. Accordingly, anydisruption of the relationship between the optical sensor and the flowmeter, such as to replace the optical sensor or to move the opticalsensor to a different position to detect a different desired flow rate,may require another complete calibration when the device is returned toservice.

Thus, there exists a need for a simple, low-cost flow-indicating device,such as a flow meter or flow switch. Such a device should desirably bereadily adaptable to various applications without having to replace theentire unit. Further, such a device should desirably remain functionallycalibrated for successive applications or replacement of components. Inaddition, the device should desirably be configured so as to minimizethe risk of contamination of the fluid.

BRIEF SUMMARY OF THE INVENTION

The above and other needs are met by the present invention which, in oneembodiment, provides a mechanism for forming a flow-indicating device.Such a mechanism comprises a shaping block adapted to operably engaged atubular body having opposed ends, wherein one of the ends is adownstream end, so as to form a constricted portion therebetween. Thebody is adapted to direct a flow therethrough and is adapted to have aflow element disposed therein. The constricted portion of the bodyformed by the shaping block thereby defines a constricted orifice havinga downstream side, wherein the constricted orifice is configured toprevent the flow element from passing therethrough and has the flowelement disposed on the downstream side thereof. The shaping block isfurther configured with respect to the body such that the flow elementengages the constricted orifice when the flow is below a flow rate andmoves toward the downstream end of the body as the flow increases overthe flow rate to thereby indicate the flow through the body.

Another advantageous aspect of the present invention comprises aflow-indicating device having a tubular body adapted to direct a flowtherethrough. The body has opposed ends, with one end being a downstreamend, and has a flow element disposed therein. A shaping block isoperably engaged with the body so as to form a constricted portionbetween the ends, wherein the constricted portion of the body defines aconstricted orifice having a downstream side. The constricted orifice isconfigured to prevent the flow element from passing therethrough and hasthe flow element disposed on the downstream side thereof. The shapingblock is further configured with respect to the body such that the flowelement engages the constricted orifice when the flow is below a flowrate and moves toward the downstream end of the body as the flowincreases over the flow rate to thereby indicate the flow through thebody. A processing device may be operably engaged with the sensor inorder to receive the signal therefrom and to perform a task in responsethereto.

Yet another advantageous aspect of the present invention comprises amethod of forming a flow-indicating device. First, a shaping block isoperably engaged with a tubular body, wherein the body is adapted todirect a flow therethrough and has opposed ends, with one end being adownstream end. A constricted portion is thereby formed between the endsand defines a constricted orifice having a downstream side. A flowelement is disposed within the body on the downstream side of theconstricted orifice, wherein the constricted orifice is configured toprevent the flow element from passing therethrough. The shaping block isconfigured with respect to the body such that the flow element engagesthe constricted orifice when the flow is below a flow rate and movestoward the downstream end of the body as the flow increases over theflow rate to thereby indicate the flow through the body.

Thus, embodiments of the present invention provide a flow-indicatingdevice, such as a flow meter or flow switch, which may be simply andcost effectively produced. Since the device is comprised of a shapingblock externally engaging a tubular body, the body may be readilyreplaced or interchanged with another similar tubular body withouthaving to replace the entire unit. Further, since the shaping blockincludes the sensor(s) for detecting the flow through the body, theshaping block remains functionally calibrated for successive replacementbodies. In addition, since the shaping block and the sensor(s) onlyexternally engage the body and do not come in contact with the flow, anadvantage in maintaining the purity of the flow may be realized. Thus,embodiments of a flow-indicating device according to embodiments of thepresent invention provide significant advantages as further detailedherein.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING(S)

Having thus described the invention in general terms, reference will nowbe made to the accompanying drawings, wherein:

FIG. 1 is a cross-sectional view of a flow-indicating device accordingto one embodiment of the present invention;

FIGS. 2A-2C are exploded perspective views of alternate embodiments of aflow-indicating device according to the present invention;

FIG. 3 is a schematic illustration of a system incorporating aflow-indicating device according to one embodiment of the presentinvention; and

FIG. 4 is a cross-sectional view of a flow-indicating device accordingto an alternate embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

The present invention now will be described more fully hereinafter withreference to the accompanying drawings, in which some, but not allembodiments of the invention are shown. Indeed, this invention may beembodied in many different forms and should not be construed as limitedto the embodiments set forth herein. Like numbers refer to like elementsthroughout.

FIGS. 1 and 2A-2C schematically illustrates a flow-indicating deviceaccording to one embodiment of the present invention, the device beingindicated generally by the numeral 10. The device 10 comprises a tubularbody 100, a shaping block 200, and a flow element 300, wherein thedevice 10 is configured to direct a flow of, for example, a gas or aliquid therethrough. The body 100 is generally configured as a circulartube, though one skilled in the art will appreciate that the presentinvention may be implemented with many different tube configurations.The body 100 may be further comprised of, for example, flexible tubingmade of a polytetrafluoroethylene material, such as Teflon®, though manyother materials may also be used where desired or necessary forcompatibility with the gas or liquid flowing through the body 100 or forcost or other considerations. In one embodiment, for example, the body100 may be transparent. The body 100 further includes an upstream end110 and a downstream end 120 through which the flow enters and exits thebody 100, respectively. Each of the ends 110, 120 have a plug 130engaged therewith, wherein the plugs 130 are configured to allow theflow to pass through the body 100.

The flow element 300 may comprise, for example, a ball, wherein the ball300 may be comprised of any suitable material such as, for instance, apolytetrafluoroethylene material such as Teflon®. The flow element 300is disposed within the body 100 and is moved along the body 100 by theflow directed therethrough. Accordingly, in embodiments of the presentinvention, the plug 130 engaged with the downstream end 120 of the body100 is additionally configured to prevent the flow element 300 fromexiting the body 100 when the flow is directed therethrough. Outward ofthe body 100, the plugs 130 may have, for example, threads and may beconfigured to sealingly engage flare fittings for connecting an inletsource 400 and an outlet reservoir 500 to the upstream end 110 and thedownstream end 120 of the body 100, respectively, as shown in FIG. 3.However, one skilled in the art will appreciate that the plugs 130 maybe configured in many different manners depending, at least in part, onthe requirements of the system in which the device is implemented. Forexample, the plugs 130 may be configured with or to accept taperedfittings, a variety of quick-connect fittings, or any number of commonlyavailable or custom-made fittings. In other instances, the plug 130engaged with the downstream end 120 may be configured such that contactof the flow element 300 therewith limits or stops the flow through thebody 100, thereby providing a high flow limiter or shut-off mechanism.

According to one advantageous aspect of the present invention, theshaping block 200 is configured to operably engage the body 100 so as tocompress a portion of the body 100 to form a constricted portion 210.For example, the shaping block 200 may comprise a first block portion220 and a second block portion 230, as shown in FIGS. 1 and 2A-2C. Insome embodiments, each of the first and second block portions 220, 230defines a groove 240 such that when the first and second block portions220, 230 are secured about the body 100, the grooves 240 define a duct250 generally corresponding to the outer dimension of the body 100.Accordingly, when the shaping block 200 is operably engaged with thebody 100, the body 100 is coaxial with the duct 250. The grooves 240further include corresponding protrusions 260 extending into the duct250 when the first and second block portions 220, 230 are engaged. Assuch, the protrusions 260 compress the body 100 to form the constrictedportion 210, wherein, if viewed axially, the constricted portion 210would define, for example, an oval orifice. The first and second blockportions 220, 230 may be secured together in many different manners suchas, for example, by fasteners 235 or, for instance, through a snaplocking mechanism, an adhesive, or in any other suitable manner.

In some instances, the dimensions of the orifice defined by theconstricted portion 210 may be adjusted by adjusting the securing forceimparted by the fasteners 235 or other securing mechanism securing thefirst and second block portions 220, 230. However, the orificedimensions, and thus the characteristics of the flow through the body100 may be adjusted by many other mechanisms as will be appreciated byone skilled in the art. For example, as shown in FIG. 4, the shapingblock 200 may further include an adjusting plate 350 disposed at orabout one or both of the protrusions 260 and adjustable into or out ofthe grooves 240. Each adjusting plate may further be adjusted withrespect to the duct 250 by, for example, an adjusting screw 360 operablyengaged therewith and adjustable from outside the shaping block 200, soas to change the dimensions of the duct 250 about the constrictedportion 210 of the body 100. Accordingly, the resulting changes in theorifice dimensions affect the characteristics of the flow through thebody 100.

One skilled in the art will appreciate, however, that the shaping body200 may be configured in many different manners to form the constrictedportion 210 when engaged with the body 100. For example, the shapingblock 200 may be configured to have two axially engaging portions, eachdefining an orifice corresponding to the outer dimension of the body100. The interface of the two axially engaging portions may beconfigured as a compression fitting such that engagement thereofcompresses the body 100 to form the constricted portion 210 which, inthis instance, would define a circular orifice when viewed axially.Further, according to another advantageous aspect of the presentinvention, the shaping block 200 is configured to form the constrictedportion 210 of the body 100 between the upstream and downstream ends110, 120 such that the flow element 300 is disposed between theconstricted portion 210 and the downstream end 120. The constrictedportion 210 is further configured such that the flow element 300 is notcapable of passing therethrough. As a result, advantageous embodimentsof the device 10 are configured such that, when no flow or a flow belowa certain flow rate is directed through the body 100, the flow element300 is disposed at the constricted portion 210 and, as the flowincreases over that certain flow rate, the flow element 300 is directedtoward the downstream end 120 of the body 100.

One skilled in the art will also appreciate that the shaping block 200may be comprised of any suitable rigid material such as, for example,metal, plastic, wood, or the like. In some embodiments, the shapingblock 200 may be comprised of a transparent polymer or plastic such as,for instance, polypropylene or polycarbonate, such that the position ofthe flow element 300 along the body 100, and thus the flow through thebody 100, can be observed and/or measured from the outside of theshaping block 200. In instances where the shaping block 200 is nottransparent, the shaping block 200 may further define a slot 380, asshown in FIG. 2C, extending between the constricted portion 210 and thedownstream end 120 to permit viewing of the position of the flow element300 along the body 100.

Another advantageous aspect of the present invention utilizes themovement of the flow element 300 toward the downstream end 120 of thebody 100, as the flow increases, to actuate other processes in thesystem associated with the device 10. In order to accomplish suchactuation, the shaping block 200 may further comprise one or morechannels 270 extending into either or both of the first and second blockportions 220, 230 perpendicularly to the axis of the body 100. Forexample, FIGS. 1-3 illustrates two such channels 270 in correspondenceacross the body 100 between the constricted portion 210 and thedownstream end 120, wherein the channels 270 may be configured toreceive, for example, a sensor 280. The sensor 280 may be directlyengaged with each channel 270 or connected thereto by, for instance,fiber optic elements 290, as shown. The sensor 280 may comprise, forexample, an optical sensor or a capacitive sensor, wherein one skilledin the art will appreciate that the shaping block 200 and the body 100may be appropriately configured to functionally accept the chosen sensortype and the sensitivity of the sensor 280 may vary according torequirements of the particular application.

FIGS. 1-3 illustrate one embodiment of the present invention, whereinthe sensor 280 particularly comprises an optical sensor configured todirect a continuous optical signal through one fiber optic element 290,across the body 100, and back through the opposite corresponding fiberoptic element 290 to the optical sensor 280. The optical sensor 280 maycomprise one of many commercially available devices such as, forexample, a Model 400-001-080 Odyssey FiberOptic Switch manufactured byFutureStar Corp. of Bloomington, Minn. Increase of the flow therebydirects the flow element 300 toward the optical signal traversing thebody 100 such that an interruption of the optical signal by the flowelement 300 is recognized by the sensor 280. As such, the channels 270and/or the sensor 280 may be configured and disposed along the shapingblock 200 such that the flow element 300 interrupts the optical signalwhen a desired flow is attained. When an interruption of the opticalsignal is recognized by the sensor 280, the sensor 280 sends acorresponding signal to a controller 600 in communication with thesensor 280. The controller 600, in turn, actuates or performs a task inresponse to the signal from the sensor 280. For example, in response tothe signal, the controller 600 may regulate or otherwise control theinput source 400 such that the flow producing the signal is maintained.In other instances, the signal may indicate a high flow or overflowsituation which would, in turn, cause the controller 600 to shut off theinput source 400. Further, in some instances, the shaping block 200 mayinclude a plurality or series of channels 270 placed at differentintervals along the shaping block 200, as shown in FIG. 2B, such thatthe flow at which the sensor 280 is activated may be adjustably selectedby selecting the channel 270 in which the sensor 280 is placed. However,one skilled in the art will appreciate that many other mechanisms foradjustably selecting the flow rate at which the sensor 280 is activated,or for viewing or otherwise determining the flow through the body 100,may be provided where necessary or desirable. For example, the shapingblock 200 may define a slot 390, as shown in FIG. 2C, configured toaccept an optical sensor 400 for measuring the flow rate through thebody 100, wherein the sensor 400 may be slidably adjusted with respectto the slot 390. Further, one skilled in the art will appreciate thatthe present disclosure describes and otherwise supports methodsassociated with embodiments of the present invention such as, forinstance, a method of forming a flow-indicating device and a method ofindicating a flow, as described and claimed herein.

Thus, embodiments of the present invention provide a flow-indicatingdevice 10, such as a flow meter or flow switch, which may be simply andcost effectively produced. Since the device 10 is comprised of a shapingblock 200 externally engaging a tubular body 100, the body 100 may bereadily replaced or interchanged with another similar tubular bodywithout having to replace the entire unit. Further, since the shapingblock 200 includes the sensor(s) 280 for detecting the flow through thebody 100, the shaping block 200 remains functionally calibrated forsuccessive replacement bodies 100 or is otherwise readily adjustable orcalibrated. In addition, since the shaping block 200 and the sensor(s)280 only externally engage the body 100 and do not come in contact withthe flow, an advantage in maintaining the purity of the flow may berealized.

Many modifications and other embodiments of the invention set forthherein will be apparent to one skilled in the art to which thisinvention pertains having the benefit of the teachings presented in theforegoing descriptions and the associated drawings. For example, theshaping block 200 may be particularly configured to be removable fromthe body 100 and applied to another body 100 of the same dimensions,wherein the sensor-flow relationship would be maintained. Accordingly,such a feature would make use of an essentially disposable body 100 anda reusable functional meter or switch portion provided by the shapingblock 200 and the associated sensor(s) 280, thereby providing asignificant cost savings over requiring an entire device for each newapplication or upon expiration of the service life of an existing unit.Therefore, it is to be understood that the invention is not to belimited to the specific embodiments disclosed and that modifications andother embodiments are intended to be included within the scope of theappended claims. Although specific terms are employed herein, they areused in a generic and descriptive sense only and not for purposes oflimitation.

That which is claimed:
 1. A mechanism for forming a flow-indicatingdevice, comprising: a shaping block adapted to operably engage a tubularbody having opposed ends, one of the ends being a downstream end, so asto form a constricted portion therebetween, the body being adapted todirect a flow therethrough and adapted to have a flow element disposedtherein, the constricted portion of the body formed by the shaping blockthereby defining a constricted orifice having a downstream side, theconstricted orifice being configured to prevent the flow element frompassing therethrough and having the flow element disposed on thedownstream side thereof, the shaping block being further configured withrespect to the body such that the flow element engages the constrictedorifice when the flow is below a flow rate and moves toward thedownstream end of the body as the flow increases over the flow rate tothereby indicate the flow through the body.
 2. A mechanism according toclaim 1 further comprising a sensor operably engaged with the shapingblock between the constricted portion and the downstream end of thebody, the sensor being configured to produce a signal in response to theflow element moving toward the downstream end of the body as the flowincreases.
 3. A mechanism according to claim 1 wherein the shaping blockfurther defines a slot between the constricted portion and thedownstream end of the body, the slot being configured to permit viewingof the flow element moving along the body from the constricted orificetoward the downstream end as the flow increases.
 4. A mechanismaccording to claim 1 wherein the shaping block is configured to besecured about the body so as to form the constricted orifice having across-sectional shape selected from the group consisting of a circle andan oval.
 5. A mechanism according to claim 1 wherein the shaping blockis comprised of polypropylene.
 6. A flow-indicating device, comprising:a tubular body adapted to direct a flow therethrough, the body havingopposed ends with one end being a downstream end; a flow elementdisposed within the body; and a shaping block operably engaged with thebody so as to form a constricted portion between the ends, theconstricted portion of the body defining a constricted orifice having adownstream side, the constricted orifice being configured to prevent theflow element from passing therethrough and having the flow elementdisposed on the downstream side thereof, the shaping block being furtherconfigured with respect to the body such that the flow element engagesthe constricted orifice when the flow is below a flow rate and movestoward the downstream end of the body as the flow increases over theflow rate to thereby indicate the flow through the body.
 7. A deviceaccording to claim 6 further comprising a sensor operably engaged withthe shaping block between the constricted portion and the downstream endof the body, the sensor being configured to produce a signal in responseto the flow element moving toward the downstream end of the body as theflow increases.
 8. A device according to claim 6 wherein the shapingblock further defines a slot between the constricted portion and thedownstream end of the body, the slot being configured to permit viewingof the flow element moving along the body from the constricted orificetoward the downstream end as the flow increases.
 9. A device accordingto claim 6 wherein the tubular body is comprised ofpolytetrafluoroethylene.
 10. A device according to claim 6 wherein theshaping block is configured to be secured about the body so as to formthe constricted orifice having a cross-sectional shape selected from thegroup consisting of a circle and an oval.
 11. A device according toclaim 6 wherein the shaping block is comprised of polypropylene.
 12. Adevice according to claim 7 wherein the sensor is selected from thegroup consisting of an optical sensor and a capacitive sensor.
 13. Adevice according to claim 6 further comprising a plug operably engagedwith the downstream end of the body, the plug being configured to retainthe flow element within the body while allowing the flow to passtherethrough.
 14. A device according to claim 13 wherein at least one ofthe flow element and the plug is configured to limit the flow throughthe downstream end of the body.
 15. A device according to claim 6wherein the flow element comprises a ball.
 16. A device according toclaim 6 wherein the flow element is comprised ofpolytetrafluoroethylene.
 17. A device according to claim 7 wherein theshaping block is configured to selectively receive the sensor therealongon the downstream side of the constricted orifice so as to allowadjustment of the flow at which the sensor responds to the flow element.18. A device according to claim 7 wherein the shaping block furtherdefines a sensor-receiving system therealong on the downstream side ofthe constricted orifice for adjustably receiving the sensor, thesensor-receiving system being selected from the group consisting of aseries of orifices and a slot and being configured to allow the sensorto be selectively placed along the shaping block to adjust the flow atwhich the sensor responds to the flow element.
 19. A device according toclaim 7 further comprising a processing device operably engaged with thesensor for receiving the signal therefrom and performing a task inresponse thereto.
 20. A device according to claim 6 further comprising aflow input apparatus connected to upstream end of the body and a flowoutput apparatus connected to the downstream end of the body.
 21. Amethod of forming a flow-indicating device, comprising: operablyengaging a shaping block with a tubular body, the body being adapted todirect a flow therethrough and having opposed ends with one end being adownstream end, so as to form a constricted portion between the ends,the constricted portion of the body defining a constricted orificehaving a downstream side; and disposing a flow element within the bodyon the downstream side of the constricted orifice, the constrictedorifice being configured to prevent the flow element from passingtherethrough, the shaping block being configured with respect to thebody such that the flow element engages the constricted orifice when theflow is below a flow rate and moves toward the downstream end of thebody as the flow increases over the flow rate to thereby indicate theflow through the body.
 22. A method according to claim 21 furthercomprising operably engaging a sensor with the shaping block between theconstricted portion and the downstream end of the body, the sensor beingconfigured to produce a signal in response to the flow element movingtoward the downstream end of the body as the flow increases.
 23. Amethod according to claim 21 further comprising forming a slot in theshaping block between the constricted portion and the downstream end ofthe body, the slot being configured to permit viewing of the flowelement moving along the body from the constricted orifice toward thedownstream end as the flow increases.
 24. A method according to claim 21further comprising operably engaging a plug with the downstream end ofthe body, the plug being configured to retain the flow element withinthe body while allowing the flow to pass therethrough.
 25. A methodaccording to claim 21 wherein operably engaging the shaping block withthe tubular body further comprises securing the shaping block about thebody so as to form the constricted orifice, the constricted orificehaving a cross-sectional shape selected from the group consisting of acircle and an oval.
 26. A method according to claim 21 wherein operablyengaging the sensor with the shaping block further comprises operablyengaging the sensor, selected from the group consisting of an opticalsensor and a capacitive sensor, with the shaping block.
 27. A methodaccording to claim 21 wherein operably engaging the sensor with theshaping block further comprises selectively operably engaging the sensorwith the shaping block along the shaping block on the downstream side ofthe constricted orifice so as to select the flow at which the sensorresponds to the flow element.